Rotary pumps



April 23 1963 G. WEISS 3,086,476

ROTARY PUMPS Filed Sept. 17, 1959 l5 IN VEN TOR. GERHART WEISS fl FIG. 5 BY M United States Patent 9 3,086,476 ROTARY PUMPS Gerhart Weiss, Mineola, N.Y., assignor to American Thermocatalytic Corporation, Mineola, N.Y., a cor poration of New York Filed Sept. 17,1959, Ser. No. 840,768 8 Claims. (Cl. 103-144) This invention relates to rotary pumps and more specifically to slider or vane pumps.

The invention is a continuation in part of Serial No. 766,896, filed October 13, 1958.

One of the objects of the invention is to reduce friction between rotating and stationary parts of the pumps substantially without affecting efficiency or output.

Another object of the invention is to reduce friction by providing a predetermined small distance or gap between rotor and housing, and filling that gapwith a substance .or layer which while offering minimum friction, will prevent the passage of the gas or fluid to be moved through the pump.

A further object of the invention is a vane pump where the vanes or blades are arranged to slide against the walls or wall portions of a housing, covered witha felt layer having fibers electrostatically applied thereto and extending into the gap, preferably substantially perpendicular to the wall'surface.

A more specific object of the invention is to arrange a number of radial blades fixedly upon a rotor shaft within a substantially cylindrical statororhousing, but

predeterminedly spaced therefrom, and to provide along a peripheral ga-p thus formed between housing and blades, a felt layer having fibers extending into the gap more or less perpendicularly to the wall surface, and substantially in the direction of the radial blades.

A further specific object of the invention is to impregnate the felt layer with a friction reducing grease.

Still another objectof the invention is to provide on other friction surfaces of the pump, especially those in contact with the radial blades, a felt layer or layers with or without grease impregnation as desired or required.

These and other objects of the invention will be more fully apparent from the drawings annexed herewith in which FIGS. 1 and 2, in side and front elevations, respectively (FIG. 1 in partial sections and FIG. 2 in full section), represent a pump embodying certain principles of the invention.

scale.

'FIG. illustrates a portion ofthe wall of the pump housing in cross section and at an exaggerated scale.

In FIGS. 1 and 2 the housing 1 of a vane pump is shown to contain supported therein a rotatable shaft 2 carrying a cylindrical rotor 3. Rotor 3 has a number of peripheral longitudinal slots 4 corresponding to the number of vanes or blades 5 which are supported rotatable substantially independent of rotor 3 on a hub 6 rotatable on or with shaft 7. Shaft 7 extends along the axis of the substantially cylindrical Work space of pump housing 1.

Both rotor shaft 7 and rotor 1 are arranged eccentrically with respect to each other in otherwise well known manner.

In this specific embodiment of the invention blades 5 are shown to be attached fixedly to or formed with hub 6. Hub 6 consists of rubber, plastic or other flexible material. This will permit peripheral displacement of 3,086,476 Patented Apr. 23, 1963 blades '5 relative to each other in the course of the movement caused by rotation of rotor 3.

'The invention, however, is not limited to the particular shape and structure nor to the relative arrangement of the rotor and stator parts shown and described.

In order for the pump to move 'a maximum amount of gas or fluid to be handled, from its suction side to its pressure side, along a predetermined peripheral part of the pump space, the peripheral gap or gaps between blades 5 and the wall of housing .1 must be reduced to a minimum.

In the embodiment shown in FIGS. 1 and 2, these peripheral gaps are arranged diametrically or symmetrically with respect to the axis of housing 1 and are designated by 9, 10, respectively. They are also arranged, preferably, symmetrically with respect to inlet and outlet 11, 12, and extend at least for gap 9, over a peripheral distance substantially equal or slightly exceeding the peripheral distance between adjacent pairs of blades 5.

Along these peripheral gaps 9, 10,'in accordance with the invention, the wall of housing 1 is coated with a felt layer consisting of an adhesive base or layer 13, 14, having fibers 15, extending therefrom into a direction substantially perpendicular to the wall surface. Fibers 15 are impregnated with a grease 16 containing a permanent type of lubricant.

In order to facilitate mounting and for other reasons, if necessary, fibers 15 may be replaced by a felt layer. Fibers T5 are applied to adhesive layers 13, 14 electrostatically in otherwise Well'known manner, and they have a predetermined length approximating and preferably exceeding the width of gaps 9, 10, respectively, 'to about .several'widths of the gap.

The adhesive layer as well as the'fibers consist of an acetate cellulose derivative which induces matting of the fibers into a dense interlocked layer which is machined to contour by .the moving parts.

Alternatively, a liquid suspension of Teflon or'nylon may be applied to the fibers before greasing.

The grease contains preferably an admixture of graphite or of molybdenum disulphite, powdered Teflon or nylon or similar friction reducing material.

Instead of cellulose acetate other adhesives may be applied which are heat and grease resistant and metal adherent.

Instead of cellulose acetate fibers, other abrasion resistant, resilient and preferably precipitable fibers may be used without departing from the scope of the invention.

Inone embodiment of the invention, blades 5 consist of plastic preferably of Bakelite including a lubricating agent, such as graphite or molybdenum disulphite.

In this case, the wall housing may consist of aluminum.

In a further embodiment of the invention, not only peripheral gaps 9, '10 are covered or coated with friction reducing felt layers 13, 14, but also other friction surfaces may be treated in a similar manner. For example, as shown in FIG. 1, the rear surface 17, is covered with a friction reducing felt layer 18, of similar structure as that shown at 13, 14, or of any other appropriate structure.

Alternatively element 20 may be made of rubber or an equivalent elastomer.

Friction in slots 4 of rotor 3 is also minimized by providing a felt insert 19 on one side, the pressure side, of blades 5, and a flexible pressure element on the other or suction side of blades 5 preferably as shown in the form of a flexible leaf, spring or metal blade 20 supported on its one or inner end in slot 21 of an inner projection 22 of rotor 3. Metal blade 20 at its other or outer end is provided with a wear surface 23 consisting of wood or felt impregnated with Teflon, nylon, graphite, molyb- 3 denum disulphite, grease, oil or other high temperature resistant permanent types of lubricant.

Pressure structure 19, 20, 21, While preferably extending longitudinally along the entire width of blade 5, may be arranged, if desired, along one or more discrete points or portions of the width of blade 5, all this Without departing from the scope of this disclosure.

Although the invention has been described and illustrated by means of specifically shaped parts or parts consisting of specific material and in specific arrangements, the invention may be applied in any other form and with any other appropriate materials and arrangements, without departing from the scope of this disclosure.

I claim:

1. A pump comprising a longitudinally extending stator having at least a part-cylindrical periphery, a shaft axially co-incident with the axis of said cylindrical portion of said periphery, at least one radially and longitudinally extending flat thin blade within said stator mounted on said shaft, means rotating said shaft about its axis, the free end of said blade when passing the cylindrical portion of said periphery being separated therefrom by a small clearance gap, an adhesive base on said cylindrical portion of said periphery, fibers adheringly embedded in said adhesive base and projecting densely therefrom towards said axis to a distance several times the gap distance between said cylindrical portion of said periphery and said free end of said blade, and means received and held by said fibers to which the free ends of said fibers adhere when bent by said blade so as to induce by the action of said blade matting of said fibers into a permanently formed smooth cylindrical surface with minimal clearance between said formed surface and said free end of said blade.

2. A pump comprising a longitudinally extending stator having at least a part-cylindrical periphery, a shaft axially co-incident with the axis of said cylindrical portion of said periphery, at least one radially and longitudinally extending fiat thin blade within said stator mounted on said shaft, means rotating said shaft about its axis, the free end of said blade when passing the cylindrical portion of said periphery being separated therefrom by a small clearance gap, an adhesive base on said cylindrical portion of said periphery, fibers adheringly embedded in said adhesive base and projecting densely therefrom towards said axis to a distance several times gap distance between said cylindrical portion of said periphery and said free end of said blade, a grease impregnating said fibers, and a lubricant admixed with said grease, said lubricant providing lubrication between said free end of said blade and said fibers, said grease coating the free ends of said fibers to cause them to mat permanently when they are bent by said blade so as to form a smooth, slippery, cylindrical surface with minimal clearance between said smooth, slippery, cylindrical surface and said free end of said blade.

3. Improvement according to claim 2, said lubricant being molybdenum disulphite.

4. Improvement according to claim 2, said lubricant being powdered graphite.

5. Improvement according to claim 2, said adhesive base being a cellulose acetate derivative, said fibers being of cellulose acetate.

6. Improvement according to claim 5, said lubricant being molybdenum disulphite.

7. Improvement according to claim 4, said lubricant being powdered graphite.

8. A pump comprising a longitudinally extending stator having at least a part-cylindrical periphery and at least one transverse end wall, a shaft axially co-incident with the axis of said cylindrical portion of said periphery, at least one radially and longitudinally extending flat, thin blade within said stator mounted on said shaft, means rotating said shaft about its axis, the free end of said blade when passing the cylindrical portion of said periphery and said end wall being separated therefrom by respective small clearance gaps, comprising an adhesive base on said cylindrical portion of said periphery and on said end wall, fibers adheringly embedded in said adhesive base and projecting densely therefrom and perpendicularly therefrom to a distance several times the gap distances between said cylindrical portion of said periphery and said end wall respectively and the respective adjacent edges of said blades, a grease impregnating said fibers, and a lubricant admixed with said grease, said lubricant providing lubrication between said free end of said blade and said fibers, said grease coating the free ends of said fibers to cause them to mat permanently when they are bent by said blade so as to form a smooth, slippery, cylindrical surface with minimal clearance between said smooth, slippery, cylindrical surface and said free end of said blade.

References Cited in the file of this patent UNITED STATES PATENTS Re. 24,932 Davey Jan. 31, 1961 305,885 Blackman Sept. 30, 1884 891,372. Reichhelm June 23, 1908 974,481 Gibson et a1 Nov. 1, 1910 1,251,095 Patton Dec. 25, 1917 2,076,536 Bateman Apr. 13, 1937 2,616,615 Scott Nov. 4, 1952 2,681,036 Ewing et al. June 15, 1954 2,706,963 Hug Apr. 26, 1955 2,754,050 Wellington, July 10, 1956 2,818,024 Herschel Dec. 31, 1957 FOREIGN PATENTS 375,789 Great Britain June 28, 1932 381,371 Great Britain Oct. 6, 1932 505,940 Germany Aug. 27, 1930 OTHER REFERENCES Circular: Static Electricity (Silsbee); Circular C438, issued June 10, l942 ,by Dept. of Commerce. 

1. A PUMP COMPRISING A LONGITUDINALLY EXTENDING STATOR HAVING AT LEAST A PART-CYLINDRICAL PERIPHERY, A SHAFT AXIALLY CO-INCIDENT WITH THE AXIS OF SAID CYLINDRICAL PORTION OF SAID PERIPHERY, AT LEAST ONE RADIALLY AND LONGITUDINALLY EXTENDING FLAT THIN BLADE WITHIN SAID STATOR MOUNTED ON SAID SHAFT, MEANS ROTATING SAID SHAFT ABOUT ITS AXIS, THE FREE END OF SAID BLADE WHEN PASSING THE CYLINDRICAL PORTION OF SAID PERIPHERY BEING SEPARATED THEREFROM BY A SMALL CLEARANCE GAP, AN ADHESIVE BASE ON SAID CYLINDRICAL PORTION OF SAID PERIPHERY, FIBERS ADHERINGLY EMBEDDED IN SAID ADHESIVE BASE AND PROJECTING DENSELY THEREFROM TOWARDS SAID AXIS TO A DISTANCE SEVERAL TIMES THE GAP DISTANCE BETWEEN SAID CYLINDRICAL PORTION OF SAID PERIPHERY AND SAID FREE END OF SAID BLADE, AND MEANS RECEIVED AND HELD BY SAID FIBERS TO WHICH THE FREE ENDS OF SAID FIBERS ADHERE WHEN BENT BY SAID BLADE SO AS TO INDUCE BY THE ACTION OF SAID BLADE MATTING OF SAID FIBERS INTO A PERMANENTLY FORMED SMOOTH CYLINDRICAL SURFACE WITH MINIMAL CLEARANCE BETWEEN SAID FORMED SURFACE AND SAID FREE END OF SAID BLADE. 